ABSTRACT MSK is committed to the discovery and development of new tools and therapeutic agents for cancer detection, prevention, and treatment. The mission of the Organic Synthesis Core is to provide chemical synthesis services to Center members through a state-of-the art facility staffed by expert professional personnel in chemical synthesis. The Core operates at the interface of chemistry, biology, and medicine, and has the capability of supporting medicinal chemistry efforts to produce and evolve lead candidates and tool compounds in support of Center investigators. The work of the Core has greatly facilitated preclinical studies at the Center. The Core synthesizes novel molecules that are not readily available, by either following described procedures, or by developing new and more suitable methods of synthesis.